Type-writer key and type-bar mechanism.



J. ALEXANDER. TYPE WRITER KEY AND TYPE BAR MECHANISM.

APPLICATION FILED JULY 15, 1911.

Patented Sept. 24, 1912] 2 snnBms-snnnr 1.

I J, ALEXANDER. TYPE WRITER KEY AND TYPE BAR MECHANISM. APPILIQATION FILED JULY 15, 1911.

2 sums-sunny a.

Patented Sept. 24, 1912.

UNITED STATES PATENT OFFICE.

JESSE ALEXANDER, OF NEW YORK, N. Y., ASSIGNOR ONE-HALF TO THEODORE A. REED AND ONE-HALF TO WILLIAM GROSVENOR RIDGWAY, BOTH OF BROOKLYN,

NEW YORK.

TYPE-WRITER KEY AND TYlE-BAR MECHANISM.

Specification of Letters Patent. Patented Sept. 24,1912.

Application filed July 15, 1911. Serial No. 638,607.

To all whom it may concern:

LO chines, and is particularly concerned with improvements in the key and type bar mechanism thereof.

The invention has for its object to provide a mechanism ofthis character which shall impart an initial movement to the type bar by a comparatively light touch upon the key lever, and which shall thereafter produce accelerated movement of the type bar to impart a firm printing blow to the platen without appreciable increase of resistance to the subsequent movement of the keylever after the initial operation of the stroke thereof.

A further object is to provide for a quick release of the type from the platen, in order to effect a clear impression, which means may be easily regulated to insure the proper position of the type with respect to the platen at the moment of imprint.

\Vith these objects'in view, the invention consists in the construction and arrangement of parts, a preferred embodiment of which is illustrated in the accompanying drawings,

in which Figure 1 is a vertical sectional view of so much of a typewriting machine as is necessary to illustrate my invention, and showing the position of the parts when the type bar is at rest. Fig. 2 1s a view similar to Fig. 1, showing the position of the parts with the type bar in the printing position.

The embodiment of my invention herein selected for illustration comprises the machine frame 1, having at the rear a transverse bar or member 2, above which the key levers 3 are pivoted at 3'. Suitable springs 4' serve to return the key levers and connected parts to initial position after the printing operation. The frame is provided also with the usual type bar segment 5. which, in the form here shown. is provided with a rearwardly curved portion 6 terminating in a forward projecting portion 7, which portions are slotted to receive the type ber 11, said member having an inclined wall- 12 to engage the cam projection 10. The

cumming members 11 rest upon'a supporting rod 13 curved to conform substantially to the curvature of the type bar segment, and thus support each of the cumming members in proper position with relation to its bar. The cumming member is pivoted at 14 to a curved link 15, which in turn is pivoted to the upstanding arm 16 of a bell-crank lever 17 pivoted on a transverse shaft 18 in the machine frame, said lever having a rearwardly extending arm 19 provided at its rear end with an ear 20 underlying. the adjacent key,lever, said arm being also slotted at 21 to engage a pin 22 on the key lever. The link 15 is curved to the rear from its pivotal connection with the eamming member 11, and its rear end is connected with thetype bar 8 by a lost motion connection comprising a slot 23 and a pin 24.

In the operation of the parts thus far described, the key lever 3 imparts initial movement to the bell-crank lever 17 through the car 20 on said lever. whereby, owing to the extended leverage, initial movementmay be imparted to the bell-crank lever 17 by an easv touch upon the key lever. In so moving, the bell-crank lever draws the link 15 and with it the cannning member 11, to the rear. whereby through the action of the cumming surface 12 of said member upon the cam projection 10 of the type bar. initial movement is imparted to the latter. By

reason of the distance of the cumming projection 10 from the pivotal point of the type, bar. the initial pressure required upon the key lever is still further decreased. After the type bar is thus started upon its printing stroke. accelerated movement is imparted thereto through the lost motion connection 23-24. which connection is located nearer the pivotal point of the type bar than the cam projection 10.

In order to effect quick release of the type bar from the platen after the printing impression. said bar is provided with a stop projection 25 which coiiperates with a corresponding stop projection or ridge 26 upon thetype bar segment 5. These stop projections may be so formed or ground as to.

check the body of the type bar just before the type reaches the platen,'whereby the spring of the upper end of the type barwillcarry the type to the laten andtrelease the same therefrom imme iately after the printing impression. The stop projections or surfaces Zia-26 are preferably made of suf ficient extent to afiorda' broad bearing for the type bar and thus prevent distortion or bending thereof, and at the same time said projections may be readily altered in height vided with a projection extending beneath said key lever adjacent the pivotal point of the latter, a lost motion connection between said key lever and said bell-crank lever at a reater distance from said pivotal point, a link ivoted to the other arm of said actuating ever and having a lost motion con nection with said type bar adjacent the pivotal point of the latter, a camming member connected with said link, and a cam projection on the. said type bar located beyond said lost motion connection and/engaged by said camming member, whereby initial movement may be imparted to said type bar by an easy touch upon the key lever, and said movement accelerated by further movemcnt'of said key lever.- V

2. In typewriter key and type bar mechanism, a frame, a type bar, a key lever therefor pivoted at the rear of said frame, a bell-crank actuating lever pivoted on said frame and having a horizontal arm provided with a projection extending beneath said key lever adjacent its pivotal point, a lost motion connection between said arm and said key lever beyond said first connection, alink pi veted to the other arm of said bell-crank lever and having 'a lost motion connection with said type baradjacent its pivotal point,- a camrning member pivoted to said link and extending forwardly therefrom, a cam projection on said type bar located beyond said lost motion connection and engaged by said carnming member, whereby initial movement maybe imparted to the type bar by easy touch upon the key lever, an the movement of the type bar may be accelerated by further movement of the key lever;

3. In typewriter key and type bar mechanism, a frame, a key lever pivoted at the rear of said frame, a bell crank actuating lever pivoted on said frame. forward of said key lever pivot and having a rearwardly extending arm provided with a projection at its rear and" extending beneath said key lever and having a lost motion connection with said key lever between said projection and the pivotal point of 'said actuating lever, said bell-crank lever having an upwardly extending arm, a link pivoted to the upper end of said second arm and extending forwardly therefrom and thence curved to the rear and'connected at its outer end by a'lost motion connection with said type bar, a camming member pivoted intermediately of said link and lying adjacent the type bar, a cam projection on said type bar located beyond the lost motion connection of said link therewith, cooperating with said member whereby initial movement of said type bar may be effected by easy touch upon said key lever, and whereby accelerated movement of said type bar may be effected by further movement of said key lever.

JESSE ALEXANDER.

Witnesses:

DAVID M. EnsALL, THEODORE A. REED.

Copies of thisrpatent may be obtained for five cents each, by addressing the Commissioner of Batents,

Washington, I). 6. 

